Machine Detail Discipline Course Project on "Belt Conveyor Drive Design"

Contents

Introduction

1. Purpose and application of the drive

2. Technical characteristics of the drive

2.1. Determination of overall drive efficiency

2.2. Determination of motor shaft speed

2.3. Determination of shaft power, speed and torque

3. Description and justification of the assigned kinematic diagram

4. Calculations confirming the operability and reliability of the structure

4.1. Defining Shaft Diameters

4.2. Selecting Bearings

4.3. Check of bearings of the most loaded shaft by dynamic lifting capacity

4.4. Key Connection Selection and Calculation

4.5. Calculation of conical wheel

4.6. Selection of gears and bearings fits

5. Design of housing parts and bearing covers

5.1. Calculation of bolts for gearbox cover connection

5.2. Distance between gear parts

5.3. Selecting Pins

5.4. Calculation of bearing covers

6. Lubrication of gears and bearings

7. Coupling selection

Conclusion

List of literature used

Applications

Introduction

The purpose of the course project is to design a belt conveyor drive consisting of an electric motor, a reduction gear, a drive shaft, a chain drive, and a coupling. The drive should be designed in accordance with the following technical condition: power supply from the AC three-phase current network with a frequency of 50 Hz and a voltage of 380V, typical loading and operation mode - IV, design life of 12000 hours, version of heat treatment of the teeth of the reduction gear box II, mass production.

Course Project Tasks:

Develop a general view of the drive (at the design stage);

Develop gearbox (at the technical design stage);

Develop detailed drawings of two parts;

Develop coupling assembly drawing;

Develop drive shaft (at technical design stage).

In this work, the belt conveyor drive is designed to transmit rotational motion from the motor to the drive shaft of the belt assembly conveyor. In production and in enterprises of different profiles, a belt conveyor is often used. Belt conveyors are used to move bulk loads over short, medium and long distances in all areas of modern industrial and agricultural production [1].

The operation of the drive begins with the fact that the electric motor is connected to the high-speed shaft of the reduction gear by an elastic clutch with a torus-shaped shell for transmitting torque, then the torque is transmitted from the slow-moving shaft through a chain drive to the drive shaft of the belt conveyor.

The advantages of the belt conveyor include, first, that it is capable of transporting the load at large angles. Also, belt conveyors have high automation and continuity of operation [1].

Purpose and application of the drive

Conveyors are machines for continuous or almost continuous flow of bulk bulk, lumped and relatively light unit loads without stopping for loading and unloading.

Conveyors make up one of the most numerous and structurally very diverse groups of continuous transport machines. Conveyers are usually used as independent loading and unloading machines. However, they are often used as components of more complex continuous vehicles.

Belt conveyors are called continuous transport machines, the carrying and traction elements of which are a flexible belt. They are used to move bulk cargo over short, medium and long distances.

The most reliable and structurally simple is a single-drum drive, since it has a small overall size, a simple structure, one bend of the tape, high reliability, but therefore a limited (up to 240°) angle of girth of the drum tape and a reduced coefficient of use of the tape strength.

The pulling force of the drum increases with increasing angle of girth, coefficient of friction and initial tension of the belt. Traction force transfer and belt movement are performed due to friction forces from drive drum.

If you compare the performance of belt and chain conveyors, the latter turn out to be more massive, complex and bulky. However, this type of conveyor equipment has much greater application possibilities, which often plays a decisive role in selecting the installation.

Thus, it becomes clear that in order to achieve the highest quality results, the use and use in the production of belt conveyors is a necessary and rational solution.

Selecting Bearings

For a high-speed wave of a reducer we will choose bearings 7209A roller conic single-row the increased loading capacity of the GOST 2736587 easy series. For them we have:

d = 45 mm - inner ring diameter,

D = 85 mm - outer ring diameter,

b = 21 mm - bearing width,

r = 1.5 mm - radius of bearing rounding,

Cr = 62700 N - dynamic load capacity,

C0r = 50000 H - static lifting capacity,

Speed: n = 1410 min-1.

Required service life L10h = 12000h

For a low-speed wave of a reducer we will choose bearings 7208A roller conic single-row the increased loading capacity of the GOST 2736587 easy series. For them we have:

d = 40 mm - inner ring diameter,

D = 80 mm - outer ring diameter,

b = 20 mm - bearing width,

r = 1.5 mm - radius of bearing rounding,

Cr = 58300 N - dynamic load capacity,

C0r = 40000 H - static lifting capacity,

Speed: n = 564 min-1.

Required service life L10h = 12000h

For drive shaft select ball radial spherical double-row bearings 1208 GOST 2842890. For them we have:

d = 40 mm - inner ring diameter,

D = 80 mm - outer ring diameter,

b = 18 mm - bearing width,

r = 2 mm- radius of bearing rounding,

Cr = 19300 N - dynamic load capacity,

C0r = 8800 H - static lifting capacity,

Rotation speed: n = 293.24 min-1.

Required service life L10h = 12000h

Conclusion

In the course design, a belt conveyor drive is designed, consisting of an electric motor, a reduction gear, a drive shaft, a chain gear, and a coupling. The drive is designed in accordance with the following technical condition: power supply from the AC three-phase current network with a frequency of 50 Hz and a voltage of 380V, typical loading and operation mode - IV, design life of 12000 hours, version of heat treatment of the teeth of the reduction gear box II, mass production.

The following are presented in the work:

General view of the drive (at the sketched design stage);

Gearbox (at the technical design stage);

Working drawings of two parts;

Coupling assembly drawing;

Drive shaft (at engineering stage).

All drive elements are mounted on a frame welded from structural steel.

The operation of the drive begins with the fact that the AIR112M4 electric motor, connected to the high-speed shaft of the reduction gear box by means of an elastic coupling with a torus-shaped shell, transmits torque of 29.71 Nm. Further, torque is transmitted from the slow-moving (previously converted as a result of the operation of the reduction gear itself to a value of 71.31 Nm) shaft through a chain drive to the drive shaft, then to the belt conveyor.

The main calculations were made in the course design, the optimal design was chosen. Calculations and parameter selection are described in this explanatory note. The graphic part of the project is presented on 4 sheets of A1 format, 2 sheets of A3 format, and 1 sheet of A2 format, and contains a calculation note and all necessary specifications.